Sunday, May 19, 2013

The old ATK speedo / odo / tripo is not compatible with the CRF front end. In looking at internet research about replacements for the stock gauges, I went with the very prevalent and affordable Trail Tech Vapor. Trail tech has great support, and answered all my questions regarding compatibility within 24 hours. Given their advice since I had a frankenstein combo of an ATK and CRF 250, I went with the 752-402 which is specific for the Honda XR series, but has cross compatibility with the CRF wheel speedo sensor, but has a simple copper ring for block temperature since I do not have a radiator line to tap into like the CRF specific kit would have included.
After getting the general placement worked out on the new dashboard, I marked the aluminum, then drilled and dremeled holes for the mounting allens and a hole for the various wire connections to pass through.
Allens tightened and wires passed.
Uh oh, looks like the brake line routing might be a problem, but tried not to stress it and continued with the install
Had to remove the Nissin caliper and drill a 1/8" hole to mount the speedo sensor. The magnetic bolt switched out easily with the stock CRF disc brake bolt.
Trying to get the unit powered by the 12V ATK system proved to be somewhat vexing. The stock connector to the ATK speedo light had 2 positive and 2 negative wires, which I assumed might be related to the key positions.
The system requires an inline 1/2 amp fuse. I opted for an inline connector from ACE and a 1/2 amp tube fuse from Radioshack.
I ended up soldering the two red wires to the inline fuse connector then to the smaller diameter red wire into the unit. The black wire i soldered to bothe black stock ATK wires as well.
Success! Power worked great, and the unit lit up bright blue when the key was turned to the full "on" position" and stayed off when only half turned. The brake line and speedo sender cable that was routed in-tandem were not an issue with screen visibility once seated on the bike.
I had a slight issue with the tachometer wire when routed alongside all of the other wires through the gap between the frame and the gas tank. There was a lot of electrical interference which caused the tach reading and speed to jump all over the place. Rerouting the wire away from all of the other electrics solved that problem and the unit has been functioning perfectly with heat warning lights and shifting signals (albeit the brake line does somewhat interfere with the visualization of these on the unit).
Part #s:
752-402 Trail Tech Vapor Stealth for XR Series
FH30B Inline Fuse Connector:
270-1018 1/2 amp Fuse:
COSTS:
Trail Tech Vapor Stealth 752-402: $93.17 from Amazon
Inline Fuse Connector: $3.84 from ACE
1/2 amp Fuse: $3.19 for 4 pack from Radioshack

Using the stock ATK dashboard with the the forks was a definite no-go, so I set out to measure, design, and mock up something that would fit want I needed (Ignition Mount, Trail Tech Vapor, and Front Brake Guide Ring).
A quick paper mock up revealed not enough rise from the lower mounts to the upper mount to span the height of the upper triple, so I had to extend it slightly.
That's better, now for trans-positioning the correct measurements to a sheet of aluminum:
Tin snips made what I thought was going to be a long and arduous wrestling match with a DREMEL very easy
The Dremel lucha libre ensued to cut out the ignition mount (notice the small square tabs for the switch to lock in when threading it in. Fortunately the areas where the Dremel ran away from me were on the underside of the dashboard (Always grind upside down when doing something you have to look at and possibly regret your unsteady hand)
I drilled some small trim holes, then wrapped and zip tied some split garden drip line to clean up the edges.
A small plastic trim ring from ACE helped clean up the brake line routing. You will need a small cut through the aluminum and trim ring to the outside edge in order to pass the brake line through, unless you plan on disassembling your brakes and re-bleeding them afterwards. I opted for the easy route!
I am really pleased with the outcome, however when riding the shiny aluminum reflects at the perfect angle to hit my eyes. Hopefully the Trail Tech will help reduce the glare.
Part #s:
5157615 8x18" Aluminum Sheet
Unknown: 1" Plastic Grommet
717089 1/4 x 50 Feeder Tubing
COSTS:
8x18" Aluminum Sheet: $8.59 at ACE
1" Plastic Grommet: $0.89 at ACE
1/4 x 50 Feeder Tubing $5.19 at Local Garden Supply Store

The part of the fork swap that is the least "plug & play" is making it so that the triple tree bolts do not piece the gas tank in the event of a "tank slapper." Usedtobefast solved this problem in a pretty sleek way by tapping to the original triple tree stops and installing bolts that would contact a welded on tab to the ATK frame before the triples contacted the tank.
I bought some bolts and went to my local art welder with pics of usedtobefast's swap hoping to recreate the same thing. After looking at the stock 490 frame steering stop steel bar welded under the downtube, we mocked up a couple of stainless ball bearings, thereby extending the stock stops ~1 cm.
Since they were round, they wouldn't ding the cast aluminum triple tress either. You can see there is plenty of room left between the triples and the tank. Left side:
Right side:
COST: $25 to the welder for at least 1.5 hours of his time

Sunday, May 12, 2013

On the recommendation of zaz696 was to keep the Brembro lever and braided cable from the stock ATK set-up, but to keep the stock CRF caliper (The brembro caliper WILL NOT mount to the stock CRF mount).
So everything mounted up nice, but after I wrestled with getting the Brembro master cylinder level multiple times, I could not get gravity to pull the brake fluid through the brake system. I fanagled a vacuum pump system with a reservoir to get enough pressure to get the fluid to overcome the resistance in the system. At this point I came to the horrible realization that fluid was pouring out of the gap between the caliper and the banjo bolt. I switched the copper washers to see if that was the problem, but on closer inspection, I realized that the banjo bolt on the caliper had been cross-threaded. My fault or the previous owner's? I would prefer to believe the latter, but I was left with the result, it was hemmorhaging brake fluid and would never retain pressure.
I started looking at new CRF calipers online, and used ones on ebay, then came to my senses and took the caliper to my local machine shop who managed to tap the threads. 25 bucks at a local machine shop was a much better alternative than a 50 dollar used caliper with who-knows what problems from ebay, or a 200 dollar new replacement.
COSTS:
$25 to machine shop for thread tapping
$5.95 for DOT 4 brake fluid to re-bleed

This went fairly smoothly, except that I wish I had 3 hands or a shop monkey to hold things in place while I grabbed a wrench or a hammer.
The headtube and triples are ALMOST a perfect fit. Per the instructions of usedtobefast and zaz696 I put 1/8" worth of 1-1/8x1-3/4x14 gauge galvanized machine bushings between the compression nut and bearing retainer (not pictured).
Each of the bushings is 1/16" and after trying 1, 2, then 3 of them, I settled on 2 (total of 1/8" and everything mated up well and the compression nut settled down nicely and the bottom bearing of the triple snugged up nicely to the headtube.
Couldn't get the plastics back on quick enough to see the big reveal:
I decided to use the CRF bar clamps as they had slightly more rise to them than the stock ATK bar clamps. This provides plenty of room to drop the forks in the triple trees without the Cycra Pro Bend mounts hitting the top of the fork tubes.
Mind you, this is not a functioning street legal motorcycle at this point. I still have to figure out the brakes, speedometer, and a few other things I'm sure that need to get sorted out before it is road-worthy.
PART # H882802 at ACE Hardware
COST: $1.50 (2 Machine Bushings @ 75 cents)

The paradox that one must face when doing this is taking a PERFECTLY FUNCTIONAL motorcycle, and deciding to rip it apart only to attempt to make it functional once again. I put this project off for a couple of weekends after getting the new front end just to get a few more rides in "just in case."
With the "last rites" out of the way, disassembly could begin:
There is no "quick guide" to taking a dual sport bike apart. I just started with the plastics.
As I got deeper, I made sue to document wire and guide positions with pictures so that when it came time for reassembly I did not rely on my memory a few days later. I used a roof rack strap to lift the intact bars / controls / electrics slightly above to old forks so I wouldn't have to rewire the whole bike. Also, important to note at this point was that I was careful to strap the back end of the bike to the MX stand and put some blocks under the rear wheel to keep everything from falling off the stand when I took the weight o the front end off of the frame.
GONE!
COST: $0

Saturday, May 11, 2013

The stock Paoli forks are really nice. I have nothing against them, but when searching for replacement parts, seals, guards, hubs, or anyone locally willing to do any service on them, I came up pretty short. I had read several entries by usedtobefast and zaz696 on the ATK RIDERS FORUM andSOUTH BAY RIDERS about swapping the Paoli or WP for CRF forks.
There have also been people like BONES and Desert Racer who have retrofit the Cannondale Ohlins forks to the single sided 605 as well.
I was pretty content to ride the Paolis until they fell apart, but then I ran across a local guy parting out a complete CRF 250f on Craigslist and after waiting to see if he could sell the complete bike for a couple of weeks, he gave up and let me know that the front end (Wheel, Caliper, Fork Legs, Triples, Bars, Master) was mine for 300 bucks.
They were re-sprung by Pro-Circuit, which I saw as a plus.
After a sketchy meeting at dusk in a Sear's parking lot, they were crammed in the back seat of the Honda and made the trip back to the shed.
COST: $300

Wednesday, May 8, 2013

In further attempts o clean up the front end, I wanted to get rid of the giant stock turn signals that came stock on the ATK. Internet perusal of options revealed Hodokaguy's post on PNWDS of fabricating the Zeta hand guard turn signals to fit into the Cycra Probend guards.
Mocking up for drilling:
Drilled, and maybe a bit too enthusiastic with the Dremel. Looking back, I would have gone a litle more gentle with a file, and not a high speed grinding wheel on soft plastic:
The stock connections pressed in nicely to the provided copper connectors provided with the Zeta replacement blinker kit:
Flush mounting with a little bit of play due to my over enthusiastic grinding. I also replaced the self tapping Cycra plastic mounting screws with stainles through bolts with locking nuts:
In the wild:
Here is a video of Hodokaguy's install (start at 50 seconds in)
Part # ZE72 3992
Cost: $36.95